5. There are therefore two sorts of Colours. The one Original and Simple, the other compounded of these. The Original or Primary Colours are, _Red_, _Yellow_, _Green_, _Blue_, and a _Violet-purple_, together with Orange, Indico, and an indefinite variety of intermediate Gradations. 6. The same Colours in _Specie_ with these primary Ones, may be also produced by Composition: For, a mixture of _Yellow_ and _Blue_ makes _Green_; of _Red_ and _Yellow_, makes _Orange_; of _Orange_ and _Yellowish Green_, makes _Yellow_. And in general, if any two Colours be mix'd, which in the Series of those, generated by the Prism, are not too far distant one from another, they by their mutual Alloy compound that Colour, which in the said Series appeareth in the mid-way between them. But those, which are situated at too great a distance, do not so. _Orange_ and _Indico_ produce not the intermediate _Green_, nor _Scarlet_ and _Green_ the intermediate _Yellow_. 7. But the most surprizing and wonderful Composition was that of _Whiteness_. There is no one sort of Rays which alone can exhibit this. 'Tis ever compounded, and to its Composition are requisite all the aforesaid primary Colours, mix'd in a due proportion. I have often with admiration beheld, that all the Colours of the Prism being made to converge, and thereby to be again mixed as they were in the light before it was incident upon the Prism, reproduced light, intirely and perfectly white, and not at all sensibly differing from a _direct_ light of the Sun, unless when the Glasses, I used, were not sufficiently clear; for then they would a little incline it to _their_ Colour. 8. Hence therefore it comes to pass, that _Whiteness_ is the usual Colour of _Light_; for Light is a confused aggregate of Rays, indued with all sorts of Colours, as they are promiscuously darted from the various parts of luminous Bodies. And of such a confused aggregate, as I said, is generated Whiteness, if there be a due proportion of the Ingredients; but if any one predominate, the Light must incline to that Colour; as it happens in the blue Flame of Brimstone, the yellow Flame of a Candle, and the various Colours of the fixed Stars.